A group of scientists have discovered that bright bedrooms could be preventing women from getting pregnant.
The researchers linked sleep habits to fertility, adding that night-time light from everything from street light creeping through the curtains to the eerie glow of tablet computers is playing havoc with the female reproductive cycle.
Middle-aged women may be particularly at risk.
The researchers advise those struggling to conceive to take simple measures to ensure a good night’s sleep. Tips include dimming the lights in the evening and having meals at regular times.
While the advice may seem odd, one in seven couples has trouble having a baby, and, in many cases, the cause is unknown.
Plus, there is growing concern that disruption to the body clock caused by artificial light is taking a heavy toll on health.
Cancer, diabetes, depression and obesity may all be fuelled by keeping the lights on at night.
British experts said link between fertility and general health should not be underestimated.
The US and Japanese researchers looked at how disrupting body clock of mice affected their fertility.
It had no effect on young mice – but pregnancy rates plummeted in middle-aged animals.
Some 71 per cent of older mice with normal body clocks got pregnant, compared to as few as 10 per cent of those whose internal, or circadian, rhythm had been disturbed, according to the journal Cell Reports.
Importantly, fertility could be restored by ensuring the creatures slept at a time in tune with their body clock.
The scientists said that while their study was on mice, the body clock may also be key to women’s fertility.
Given that it is set by the sun, avoiding sources of artificial light at night could boost chances of conception.
Researcher Dr Gene Block, of the University of California Los Angeles, said: ‘In modern society, females are exposed to many challenging perturbations in the environment that may play a role in fertility difficulties.
‘We now live with high light levels in the evening and our sleep cycle is disrupted by shift work or crossing time zones.
‘The ability to rescue reproductive function by altering the light schedule in a rodent model suggests that improvements in “circadian hygiene”- for example, reductions in evening illumination, more regular meal timing, or avoiding rotating shift work or schedules that lead to irregular sleep – may all be important remedies for reproductive difficulty.’
Dr Neil Stanley, an independent sleep expert, said the body’s rhythms are ‘exquisitely timed’ and we should not be surprised that fertility is linked to the sleep cycle.
Professor Darren Griffin, of Kent University, described the research as a ‘significant advance’.
He added: ‘It is particularly exciting given the fact that the situation seems to improve when the circadian rhythms are rectified.
‘The usual caveats apply – humans are not mice, and light-dark cycles may only be part of the story.
‘Nonetheless, the message that fertility is related to general health and wellbeing should not be underestimated.’
Source: Daily Mail